rob vanharten

Could it actually need more prop and be hitting a rev limiter? Excuse my ignorance, my last boat had warmed up carb hp500's that made 600hp at 5600 rpm's. Why would the 280 hit 78 gps on a labbed 29 and then hit a wall at 73 with a stock 28p. The motor runs excellent, and sounds very healthy!

Powerquest230

Based on the 500EFI pushing the same hull to 71 and baja27's friend hitting low 80's with 700hp- sounds like the 509 is making less power than advertised.

abones

seems to be abnormaly high slip, around 18% could be something going on with the prop, or driver error, bad gps #s, but with 12% slip it would come in at close to 80 MPH.

I Had an 88 Convincer with a B&M blower, #2 speedy, hand built cleaver, It ran mid 80s all day every day, 92 with the NOS. way back when, so the boat in question should at least run 80 IMO.

flysfloatsor

iTrader: (-1)

Was this the boat in Indianapolis?

If so, It looks like a nice ride.
BTW - IMHO, a guy who spends that much on nice cover/covers for the boat likely takes care of the rest of it.

rob vanharten

[QUOTE=flysfloatsor;3804929]Was this the boat in Indianapolis?

If so, It looks like a nice ride.
BTW - IMHO, a guy who spends that much on nice cover/covers for the boat likely takes care of the rest of it.

Yes this is the boat out of Indy. The boat has been taken very good care of, and this Gentleman is a stand up guy, and I do not think for a second he is trying to hide something. The boat appears to be everything he says it is, and the boat speaks for itself. It really does run awesome!!! Something just seems a little off. Maybe it was just a bad gps or something stupid like that. But 28p 4 blade, with a 1.5 ratio drive and currently spinning it to 5100 should be more than 72..........?

flysfloatsor

iTrader: (-1)

Ran the numbers and 72 @ 5100 w/ 28 prop is a Shade over 20% slip.

Something is off.

One of three is broke - Prop, tach, GPS.
Id still buy it if I had the cash (Def over the 525efi one for $68k)

indywhsle

Hi Rob, I got your pm and as others have said the numbers don't add up. As you know I had a 98 baja 272 with a 509 and a m3 procharger. When I sold it it had a stock bravo 1 drive. It dynoed at 729hp at 5300rpm and 775 ft-lb torque at 4600 rpm. The guy I sold it to is in Florida and told me he had it in the low 90's but it was a little scary. The prop was a stock 30p bravo. He did add a -2 imco lower, imco upper, and hydro steering. If the boat you bought really has the power you are saying then it should have had the computer reprogramed and be running way more rpm and speed. The rev limit on mine was set at 5600. I will attach a build sheet. Call me when you get a chance.

rob vanharten

Thanks Mike, I was at work and could not answer when you called. I will give you a shout tonight!!!

rob vanharten

Okay things are making sense now. Mike, the engine is built identical to yours same builder same spec sheet,except is was programmed and tuned on 5 pounds of boost. I get the smaller pulley and belt to make 7-8 pounds with the boat. Should make about 675hp on the current 5 pound setup. Anyways I just got off the phone with a good friend of the boats owner who I also know and is a bit of an icon here in the west MI area. He knows the boat very well, and is very knowledgeable in high performance marine. He said this boat is everything it appears to be, and runs very strong! He said the boat runs VERY wet, and may just need to trim the boat a little more, or possible play with the prop depth a little bit. But assured me the boat was spinning a 28b, at 5100, and suffering from alot of prop slip. He observed all of this while spending a whole day on the boat. Anyways, with a little tweaking we should be 80mph +, I am pretty stoked!!!!!!!

rfgonzo

Rob, cogratulations on the boat, but what happend to gitting a boat that goes 100MPH? LOL